and Integrated Pest Management - part - usaid

FUIURE NEEDS FOR PESTICIDE MANAGEMEFT IN SOUT EAST ASIA 3
poisoning from the highly toxic dust of carbofuran granules (Anon. 1985). In
Indonesia, from April 1985 to March 1986, cases of death and poisoning due to
pesticides were 62 and 324 persons respectively (Directorate of Food Crops
Protection 1986). Pesticide poisoning may occur (luring the manufacture and
formulation of pesticides, while loading sprayers or, most frequently, during the
actual application of pesticides on crops. Farmers are exposed through dermal
contact and inhalation of fine particles or vapor, particularly in developing
countries where most farmers are unaware of the toxic nature of pesticides.
Protective clothing has been designed, such as a completely closed mask that
circulates air through a filter and which can be equipped with a refrigeration
system for use in warm climates (Yates et al. 1981). lowever, most Southeast
Asian farmers may not be able to afford such adevice. Other cases of accidental
poisoning are exposure to pesticides during storage and transportation, and
contamination of foodstuffs. Accidents may also arise from spillage of
pesticides in storage and transportation and from the use of unlabeled pesticides
by mistake for food and drink (Oka 1983). In villages, pcople bathe or wash
their clothing in irrigation drainage canals or rivers that may be contaminated
with pesticides originating from nearby rice fields. We suspect that there may be
cases of chronic toxicity, cancers, spontaneous abortion or abnormal offsprings,
but unfortunately no documented reports are available.
The development of pest resistance to pesticides has been demonstrated in 16
orders of arthropods totalling 428 species (Georghiou & [lellon 1983). A pest
may become resistant to one Formnlation of pesticides, to chemically related
pesticides (cross resistance), or to a variety of insecticides with differing modes
of action-detoxification pathways (multiple resistance). All the above seriously
limit the choice of available pesticides (Litsinger & Sanchez 1984). Most of the
work on the resistance of a number of rice insects to pesticides has been clone in
Japan (Nagata & Mochida 1985). Data on insect resistance to pesticides in
Southeast Asia are rare. Brown planthoppers in the Philippines have been
reported resistant to BPMC, acephate and chlorpyrifos-BPM/lC (Mochida &
Basilio 1983); and to carbaryl, carbofuran, diazinon, and malathion (IRRI 1984).
The GLI-I in Indonesia was reported to be resistant to fenitrothion, diazinon, and
carbaryl (Merthakota & Sutrisno 1982). The diamondback moth Plutella
xylostella has most likely developed multiple resistance to insecticides in
Indonesia since various pesticide formulations have become ineffective.
Extensive studies have been carried out on the resurgence of BPH in the
Philippines (Chelliah & l-leinrichs 1980) and in Indonesia (Oka 1978, Soekarna
1979, 1981). Destruction of the natural enemies of the insect duce to intensive
application of broad spectrum insecticides, the phytotonic effect of certain
pesticides (Chclliah & Heinrichs 1984), and increased feeding rates, and
stimulation of BPH reproduction clue to some pesticides (Chelliah 1979,
Chclliah & Heinrichs 1980) are some of the factors causing BPI-I resurgence.
Also, pesticide application at sublethal dosages (Chelliah 1979), differential
insecticide rates (Chelliah & Heinrichs 1984) and timing, and the number and
methods of application can induce BPH resurgence (Heinrichs et al. 1982). To
date, all classes of insecticides studied have been identified to induce resurgence